2000BaltA...9...13O

In recent years, Whole Earth Telescope observations led to determination of mass and luminosity for the majority of the GW Vir pulsators. We find that pulsators of low mass have higher luminosity, suggesting the range of instability is highly mass-dependent. The observed trend of decreasing periods with decreasing luminosity matches a decrease in the maximum (standing-wave) g-mode period across the instability strip. We show that the red edge can in fact be caused by the driving period increasing beyond the maximum sustainable period of standing waves.